1. A method for the separation of UDP-N-acetylglucosamine from UMP and N-acetylglucosamine by high-pressure liquid chromatography utilizing an anion exchange resin is being developed. 2. When this method of separation has been worked out, the enzymatic hydrolysis of UDP-N-acetyl-(14C)glucosamine by sonicates of cultured normal hamster cells, cultured rat-embryo cells and of rat-embryo cells transformed in vitro by certain carcinogenic fluorenylhydroxamic acids and their respective acetate esters will be investigated. There is one unconfirmed report in the literature that the above enzymatic hydrolysis is blocked or deleted in cells transformed by oncogenic viruses or chemical carcinogens. We are pursuing this problem in our attempt to obtain early objective evidence of cellular transformation by chemical carcinogens. 3. Attempts are in progress to isolate and characterize a microsomal protein induced by systemic administration of N-2-fluorenylacetamide (2-FAA) to the rat. Preliminary evidence suggests that this microsomal enzyme N-hydroxylates 2-FAA (and possibly other arylamides). 4. Several routes for the synthesis of O-acylfluorenylhydroxylamines are being explored. These compounds are reputed to be the ultimate carcinogens of fluorenylamides. The evidence is circumstantial and no direct tests of this hypothesis have been possible because of the unavailability of these compounds.